Vibrator for use in connection with concrete



R. L.'wlLDE VIBRATOEZRUSE 1N cQNNEcTIoN WITH CONCRETE Nov. 23, 1948.'

Filed Jan. e, 194? IN V EN TOR.

POBEPT [..W/LDE Y ATTORNEY Patented Nov. 23, 1948 IuNrrrlsjD STATES -PATENT ori-ice vV'IBIRA'IDR FORQUSE IN CONNECTION WITH CONCRETE Robert L. wilde, Englewood, ocio.

Application January 6, 1947, Serial No. 720,455 n 2. Claims. 1

This invention relates to improvements in high speed vibrators for vibrating concrete and the like.

Experience has yshown 'that concrete formed from aggregate and Portland cement, for example, in `order to have the 4most desirable properties, for exampler the greatest density and imperviousness to moisture, as well as the greatest strength, requires it to -be Vsubjected to intense Vibrations after it has been put in place in the forms so as to effect a consolidation of the particles and a complete filling of all interstices.

The former practice of making the grout quite Wet to make the materials ow together readily and then `su`r ject it to tamping and the action of gravity, has been found to be erroneous for various reasons, oneof which is that the excess liquid present in such a mixture carries with it a considerable proportion of the cement yand therefore leaves the resultant concrete with less 4the least possible in response to the centrifugal than the necessary amount for the best results.

There may be, and perhaps are, other reasons Why vibration'results in a'better concrete.

Vibrators, to be eifective for 'the purpose under considerably lower than this are used and also if much higher speeds are used, the rate of vibration seems to be so different that the vibrator soon forms a hole or cavity in which it rests, but in which it is not in contact With the concrete except at portions of its area. It has been found that vibrators ,that are required to vibrate at such a high speed 4cannot be successfully lubricated with ordinary grease and thatthey therefore Wear out very quickly.

'It ,is an object of .this invention to produce a vibrator in which the eccentric Arotary element is partially immersed in oil of .a suitable weight when it is not in use and functions as a distributor Vand sets 4up forces that causes the oil to enter the bearing so as to maintain agood 'lubricating film between the moving surfaces when the vibrator is operated.

It is a further .object `of this invention to produce a vibrator in which the eccentric, elongated,

rotating element is vso designed .that .it will .iiexl forces set up during `such rotation.

Another Objectis to produce a rotary element of such cross 'section that it will move through the lubricating oil with the least amount of friction 4and cause the 'least possible disturbance of the oil.

A still further object is to produce a vibrator of the type having an elongated cylindricalbody which contains the rotary element and Awhich is of such construction that it can be hermetically sealed so as to `retain the oil in position.

still further object'of the invention is to produce a vibrator that can be readily attached to aflexible shaft and in which the means for effecting Vsuchconnection is of a construction that permits the jparts to readily adjust themselves to Variations in length of the shaft due to bending.

`Another Vobiect'isto produce a vibrator having one vend provided with a chamber for storing the lubricating oil when the vibrator is in use and from which `vit -will quite readily flow so as `to permitit to enter lthe chamber when the vibrator is inoperative.

'The above and other objects that may become apparent as this description proceeds are attained by means of a construction `and an arrangement of parts that will now be described in detail and for this purpose reference Will be had to the accompanying drawings in which the invention has been lillustrated in its preferred embodiment and *in which:

Figure l is a longitudinal diametrical section;

Figure 2 is a section taken` on line 2--2, Figure i1;

Figure 13 "is a section taken on line 3 3, Figu-re 1; and p Figure 4 `iis a section taken on line 4 4, Figure v1.

. In the .drawing :reference numeral -5 designates thesouter tubular portion of a flexible shaft whose power ltransmitting felementfhas been designated by meter-ence numeral 6.. The actual construction ofithisfflexilblefshaft has not been shown k.because it forms no part of the invention and such shafts can 'be purchased on fthe Lopen market. The .ilexible shaft terminates .in `a coupling like ythat designated :by reference numeral 1 which has an anti-friction bea/ring 8 .in vwhich the cylindrical member 9 rotates. `Coupling 'l terminates vin a cylindrical portion t0, whose vouter surface is threaded for connection with the "cylindrical connector element ILV-which will be hereinafter :de-

scribed in greater detail.` The vibrator properv consistsaf asteel tube or .hollow cylinder .I2 havi ing one end provided with an internally threaded coupling I3, which may be soldered to element I2 along the line indicated by reference numeral I4. The outer end of hollow cylinder I2 is closed by member I5 which is welded or soldered thereto along line I 6. The extreme end of member i 5 has a threaded opening for the reception of plug I1. The inner surface of cylinder I2 is provided adjacent the closed end with an internal groove I8 for the reception of a split ring that forms shoulder I 9 against which the outer race of antifriction bearing 2S abuts. The eccentric rotor that produces the vibrations, consists of an elongated steel member 2I that terminates in trunnions 22 and 23, the inner bearing races i'lt over the trunnions as shown in the drawing. Trunnion 23 at the lower end, when viewed as in Figure l, carries an anti-friction bearing that can slide in cylinder I2. The trunnion near the upper end of the vibrator, when viewed as in Figure 1 is provided with an axial opening that has been designated in the drawing by reference numeral 24. The cup-like nut 25 has its outer end provided with a lnoncircular andpreferably a hexagonal socket 26 and is preferably welded to trunnion 23 so as to prevent accidental rotation thereon. y

The short cylindrical connector element II is provided at its upper end with a threaded surface 21 by means ofr which connection may be eifected between it and the connector I3. An anti-friction bearing 28 is positioned in connector element II Bearing 28 abuts shoulder 29 and is held in position by the inwardly projecting flange 30. A hollow spindle 3| is mounted for rotation in bearing 28 as shown in the drawing. The upper end of this spindle terminates in a hexagonal plug 32 that ts socket 26 with a slight clearness to permit such slight relative movements as are produced when the vibrator is operating.

Referring now again to the elongated rotating element 2l', it will be observed that practically all of this is positioned to one side of the axis of rotation as shown, for example, in Figure 2. For the purpose of strengthening this element so as to limit the outward bending, in response to centrifugal force, to as small an amount as practicable, the central portion has been formed with an inwardly bowed part like that designated by reference numeral 33, the section at the maximum thickness being like that shown in Figure 3. Spindle 22 has an axial opening 24 which interconnects the rotor chamber with the oil reservoir for a purpose that will presently appear. Hollow spindle 3i has a hexagonal opening 34 for the reception of the correspondingly shaped plug 35 at the end of member 9. It will be observed that plug 35 has considerable longitudinal movement relative to the spindle and therefore no appreciable strains can be set up due to bending of the exible shaft or due to any slight elongationl or contraction of the same or any of the other parts in response to temperature differences.`

In the operation of this vibrator, the reservoir atthe upper end, when viewed as in Figure l, is supplied with a quantity of oil sufficient to lill it and this will ilow through opening 24 and between the anti-friction elements of the bearing and into the rotor chamber, when the vibrator is lying on a flat surface. When the vibrator is positioned With closed end I5 at the bottom, practically all of the oil will drain back into the reservoir leaving only the oil that adheres to the rotor and other surfaces. When the vibrator is in operation, the high speed at which the rotor turns distributes the adherent oil to all of the bearings and this keeps the parts properly lubricated during each period of operation, when the vibrator is laid down on the ground or other supporting surface, between operations, the oil in the reservoir is again distributed over the parts thus renewing the lubrication to all thebearings.

Attention is again directedto the construction by means of which the rotatable parts are all thoroughly lubricated at the beginning of each period of use. Vibrators of this kind are nearly always operated with the end which is shown at the top in Figure 1 lower than the end to which the flexible shaft is connected. By the expedient above described of providing the closed end with a reservoir into which the oil can rel treat at the beginning of each period of operation and from which it can flow when the vibrator is laid down fiat, the oil i-skept out lof the way of the rotor during the time that it is operating and is not worn out needlessly. Since-V the roter is positioned almost wholly on one side ot a diametri-cal plane, it will naturally assume a position below the horizontal diametrical plane' when at rest and therefore a compara?l tively small quantity of oil is sufcient to-ll the space between the rotor and the housing.

It is essential that the vibrator be perfectly i5 may be soldered instead of welded and is the only one that is completed after the parts are in place. The distance between bearing 20, 2 i' and joint I5 is so great that the heat will not injure the bearing. It is, however, possible to immerse the vibrator in Water up to bearing 20, 2l while welding at I6.

Having described the claimed as new is:

1. A mechanical vibrator comprising, an elongated housing having one end closed, an elongated eccentric vibrator positioned in the housing, each end of the vibrator having an antifriction bearing supported by the inner surface of the hou-sing, one of said bearings being spaced rom the closed end forming an oil reservoir. said last mentioned bearing having an opening communicating the reservoir with the space between the bearings, wherebyoil from the reservoir will flow into the space between the bearings when the vibrator is positioned in a horiinvention, what is zcntal plane, and return to the reservoir when ings positioned therein, in longitudinallyv spaced relation, one adjacent each end, an elongated unbalanced rotor having trunnions at its ends mounted for rotation in the bearings, and means at one end for turning the rotor, means for automatically applying a lubricant to the bearings when the device is in horizontal position, com prising an extension of the hou-sing beyond the bearing at the end of the housing opposite from the rotating means, forming a lubricant reservoir, the trunnion at the lubricant reservoir end having an axial opening communicating the interior of the reservoir with the rotor chamber, whereby any oil in the rotor chamber when the device is in horizontal position will drain back into the reservoir when the device is in an upwardly ranging position with the reservoir at the lower end.

ROBERT L. WlLDE.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES lPATENTS Number Name Date 1,989,409 Gordon Jan. 29, 1935 Number Number 

